1. Field of the Invention
The present invention relates to an apparatus and method for isotonic exercise as used in strength training, and more particularly, to exercise performed using a rolling apparatus.
2. Description of Related Art
Isotonic exercise involves the movement of a body part against resistance. Different isotonic exercise methods are known in the art. Some methods, for example, push-ups and sit-ups, make no use of exercise equipment. Other methods make use of equipment, such as barbells, tension bands, springs, or rollers. Such equipment is often used to increase the resistance or level of difficulty of the workout, such as to achieve superior strength conditioning more quickly.
Some methods of isotonic exercise involve the use of a roller incorporated into exercise equipment. Typically, the user performs an exercise by moving the roller over a track in a back-and-forth motion, working against a spring or gravitational force. Movement of the roller against a resistance permits a cycle of contraction and extension for the desired muscle group. Muscle groups that are sometimes conditioned this way include abdominal, back, arm, and leg muscles. Rolling apparatus, for example, roller skates and skateboards, are also used as play or sports equipment, but such uses are distinct from isotonic exercise.
Although methods and apparatus for isotonic exercise using rollers are beneficial for strength conditioning, they are subject to certain limitations. After a period of use, a user may become bored with the repetitious back-and-forth motion used in rolling exercise. Certain muscle groups may be difficult to exercise using a traditional rolling apparatus, for example, it may be difficult or impossible to achieve a desired relationship between a path of motion of the roller, and a muscle group to be exercised. It may be desirable to exercise a wider range of muscle groups using a single exercise than is possible with a conventional roller. For example, it may be desirable to perform a more complex, motion cycle using a rolling apparatus. A more complex motion may be used to involve a greater number of muscle groups in a particular exercise. In addition, a more complex motion can be used to develop both muscle coordination and strength with a single exercise. A back-and-forth rolling apparatus may place undesirable constraints on the performance of these more complex exercises.
It is desirable, therefore, to provide an apparatus and method for performing an isotonic exercise that overcomes the limitations of the prior art.